1. Field of the Invention
The present invention relates generally to packaging arrangements for packaging products such as contact lenses in packages such as blister packs.
More particularly, the subject invention pertains to a packaging arrangement having an intermittently indexed, linearly driven endless conveyor which includes a plurality of identical support pallets, equally spaced apart along the movable conveyor. Each support pallet is designed to support a 2.times.5 array of individual package bases thereon, and is sequentially stopped at spaced work stations along the packaging arrangement. At a first station, a robotic loader arm loads blister package bases, each having a product deposited therein, in the support pallet then at the first station. At subsequent spaced stations, the packaging arrangement optically inspects the loaded pallet for skewed (improperly positioned) package bases, optically verifies the presence of a package base at each array location in the pallet, deposits a fixed dosage of saline solution into each package base, optically verifies that a proper dosage of saline solution has been deposited into each package base, places a laminated foil cover sheet over each 1.times.5 row of package bases, mechanically chucks each laminated cover sheet to properly position it relative to the row of package bases, optically verifies the presence and proper positioning of each laminated cover sheet, heat seals each laminated cover sheet to a row of package bases, optically inspects each heat sealed laminated cover sheet for proper positioning relative to the row of package bases, and finally unloads each row or strip of completed blister packs from the endless conveyor for subsequent processing such as sterilization and secondary packaging.
2. Discussion of the Prior Art
The prior art discloses the use of linear conveyor arrangements and also rotary index tables in packaging equipment, the packaging of contact lens in blister packs with saline solution, and the checking of various packages by a variety of optical probes. Moreover, the prior art also discloses heat sealing lids or covers to container bases. However, in most prior art methods of heat sealing, the temperature of the sealing heads are generally maintained at lower temperatures, and the sealing heads are generally applied for longer periods of time as compared with the present invention. In one prior art approach, a pneumatic cylinder pressed a heated sealing head against the covers being applied to package bases, and a load cell feedback system measured the load on the pneumatic cylinder, which started a measured heater timing period.
The present invention is related to patent application Ser. No. 08/257,787, filed Jun. 10, 1994, for a Packaging Arrangement for packaging products such as contact lenses in blister packs. The packaging arrangement disclosed therein includes a rotary index table defining on its upper surface a plurality of identical, radially-oriented support pallets, equally spaced apart around the rotary index table. Each support pallet is designed to support an array of individual package bases thereon, and is sequentially rotated to stop at angularly spaced radial positions in the rotary packaging machine. At a first radial position, blister package bases, each having a product deposited therein, are placed in the support pallet then at the first radial position. At subsequent radial positions, the rotary packaging machine verifies the presence and alignment of each package base, deposits a fixed dosage of saline solution into each package base, optionally verifies that a fixed dosage of saline solution has been deposited in each package base, places a marked laminated cover over the package bases, heat seals the laminated cover to the package bases, verifies the proper positional placement of the laminated cover on the package bases, and finally unloads the completed blister packs from the rotary packaging station for subsequent processing such as sterilization and secondary packaging.
Such a rotary packaging station has a plurality of angularly displaced work stations, some of which must interface with outside equipment such as robotic handling arms, which can present problems with positioning alignment and space allocation. In contrast thereto, the linearly driven endless conveyor of the present invention is much easier and simpler to design and to interface with associated handling and supply equipment such as cartesian (x,y) robotic handling equipment.